Table 2.
Prevalence of congenital heart defects according to ambient temperature 2–8 weeks postconception, Quebec, April through September, 1988–2012.
| Type of heart defect | No. of days ≥ 30°Ca | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| 0 days (N = 218,337) | 1–2 days (N = 182,430) | 3–9 days (N = 262,300) | ≥ 10 days (N = 41,142) | Trend p-valueb | |||||
| No. infants with defects | Prevalence per 100,000 (95% CI) | No. infants with defects | Prevalence per 100,000 (95% CI) | No. infants with defects | Prevalence per 100,000 (95% CI) | No. infants with defects | Prevalence per 100,000 (95% CI) | ||
| Critical defect | |||||||||
| Tetralogy of Fallot | 44 | 20.2 (14.6, 27.1) | 32 | 17.5 (12.0, 24.8) | 53 | 20.2 (15.1, 26.4) | 9 | 21.9 (10.0, 41.5) | 0.8 |
| Transposition of great vessels | 42 | 19.2 (13.9, 26.0) | 33 | 18.1 (12.5, 25.4) | 37 | 14.1 (9.9, 19.4) | 12 | 29.2 (15.1, 50.9) | 0.8 |
| Truncus arteriosus | 12 | 5.5 (2.8, 9.6) | 5 | 2.7 (0.9, 6.4) | 14 | 5.3 (2.9, 9.0) | 5 | 12.2 (3.9, 28.4) | 0.3 |
| Hypoplastic left heart | 24 | 11.0 (7.0, 16.4) | 18 | 9.9 (5.8, 15.6) | 31 | 11.8 (8.0, 16.8) | < 5 | 4.9 (0.6, 17.6) | 0.8 |
| Common ventricle | 6 | 2.7 (1.0, 6.0) | 8 | 4.4 (1.9, 8.6) | 6 | 2.3 (0.8, 5.0) | < 5 | 2.4 (0.1, 13.5) | 0.7 |
| Coarctation of aorta | 36 | 16.5 (11.5, 22.8) | 38 | 20.8 (14.7, 28.6) | 39 | 14.9 (10.6, 20.3) | 9 | 21.9 (10.0, 41.5) | 0.9 |
| Other | 19 | 8.7 (5.2, 13.6) | 12 | 6.6 (3.4, 11.5) | 19 | 7.2 (4.4, 11.3) | < 5 | 7.3 (1.5, 21.3) | 0.6 |
| Any | 172 | 78.8 (67.4, 91.5) | 141 | 77.3 (65.1, 91.1) | 187 | 71.3 (61.4, 82.3) | 39 | 94.8 (67.4, 129.6) | 0.9 |
| Noncritical defect | |||||||||
| Endocardial cushion | 33 | 15.1 (10.4, 21.2) | 34 | 18.6 (12.9, 26.0) | 40 | 15.2 (10.9, 20.8) | 5 | 12.2 (3.9, 28.4) | 0.8 |
| Ventricular septum | 617 | 282.6 (260.8, 305.8) | 546 | 299.3 (274.7, 325.4) | 755 | 287.8 (267.7, 309.1) | 116 | 282.0 (233.0, 338.1) | 0.9 |
| Atrial septum | 631 | 289.0 (266.9, 312.4) | 584 | 320.1 (294.7, 347.1) | 867 | 330.5 (308.9, 353.3) | 170 | 413.2 (353.5, 480.0) | 0.0001 |
| Valve | 62 | 28.4 (21.8, 36.4) | 73 | 40.0 (31.4, 50.3) | 99 | 37.7 (30.7, 45.9) | 13 | 31.6 (16.8, 54.0) | 0.2 |
| Aorta | 26 | 11.9 (7.8, 17.4) | 22 | 12.1 (7.6, 18.3) | 43 | 16.4 (11.9, 22.1) | 8 | 19.4 (8.4, 38.3) | 0.1 |
| Pulmonary artery | 174 | 79.7 (68.3, 92.4) | 163 | 89.3 (76.2, 104.2) | 230 | 87.7 (76.7, 99.8) | 29 | 70.5 (47.2, 101.2) | 0.8 |
| Heterotaxy | 18 | 8.2 (4.9, 13.0) | 17 | 9.3 (5.4, 14.9) | 20 | 7.6 (4.7, 11.8) | 6 | 14.6 (5.4, 31.7) | 0.7 |
| Other | 487 | 223.0 (203.7, 243.7) | 384 | 210.5 (190.0, 232.6) | 620 | 236.4 (218.1, 255.7) | 105 | 255.2 (208.8, 308.9) | 0.1 |
| Any | 1,753 | 802.9 (765.9, 841.2) | 1,552 | 850.7 (809.1, 893.9) | 2,261 | 862.0 (827.0, 898.1) | 377 | 916.3 (826.5, 1013.2) | 0.007 |
| No. of defects | |||||||||
| Single | 1,613 | 738.8 (703.3, 775.6) | 1,399 | 766.9 (727.3, 808.0) | 2,050 | 781.5 (748.2, 816.0) | 323 | 785.1 (702.1, 875.1) | 0.09 |
| Multiple | 306 | 140.2 (124.9, 156.8) | 282 | 154.6 (137.1, 173.7) | 391 | 149.1 (134.7, 164.6) | 80 | 194.4 (154.2, 242.0) | 0.07 |
| Any | 1,919 | 878.9 (840.2, 919.0) | 1,681 | 921.4 (878.1, 966.4) | 2,441 | 930.6 (894.2, 968.1) | 403 | 979.5 (886.6, 1079.5) | 0.02 |
| aNumber of days with maximum daily temperature ≥ 30°C during weeks 2–8 postconception. bCochran–Armitage trend test. | |||||||||